Service\WikiNodeRevision
https://github.com/neurocracy/drupal-omnipedia-core/blob/ba9a617d1b90491f8719759abcacc723073d0126/src/Service/WikiNodeRevision.php#L57
TBD.
https://github.com/neurocracy/drupal-omnipedia-core/blob/ba9a617d1b90491f8719759abcacc723073d0126/src/Service/WikiNodeRevision.php#L99